JPH0514191Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[0001]

[Field of Industrial Application] The present invention relates to a temperature/liquid leakage detection line that can be used both to detect abnormal temperatures of a detected object and to detect liquid leakage.

[0002]

[Prior Art] Fire alarms and sensors for detecting liquid leakage are sometimes installed in structures such as buildings and mechanical equipment for fire prevention and flood prevention purposes. However, it is necessary to separately provide dedicated sensors for each, and this poses a problem in that wiring becomes difficult when installing the various sensors. Moreover, many of the conventional sensors are
Since the system detects an abnormality at a single point, in order to detect an abnormality over a wide area, a large number of sensors must be installed, which poses the problem of increasing the cost of disaster prevention equipment.

【0003】

[Problems to be solved by the invention] The present invention has been made in view of the above-mentioned problems. It is an object of the present invention to enable one sensor to detect an abnormality over a wide range when it occurs.

[0004]

[Means for solving the problem] The temperature and
In order to achieve this purpose, the liquid leakage detection wire is constructed by covering both the first and second linear bodies with an external braided body made of liquid-absorbing thread, and The first linear body is constructed by sequentially covering a plastic optical fiber with a conductor made of a metal braid and an inner braid made of synthetic fiber yarn, and the second linear body is made of a plastic optical fiber. It is constructed by covering the body with an internal braided body made of synthetic fiber yarn.

[0005]

[Function] The temperature/liquid leakage detection wire of the present invention has a braided body around the plastic optical fiber and the outer periphery of both linear bodies, so the air permeability between the outside and the optical fiber is good. When at least a portion of the object to be detected, on which the temperature/leakage detection wire is installed, becomes overheated and the temperature of the surrounding air rises, the surrounding air is smoothly guided to the optical fiber section and its temperature increases. The increase in temperature is immediately transmitted to the plastic optical fiber, and as a result, when the temperature of the plastic optical fiber reaches above its softening temperature, the overheated portion locally softens, contracts, and breaks. For this reason, the optical signal from the light source is no longer transmitted midway through, and an abnormality is detected by a photodetector connected to the plastic optical fiber.

[0006] On the other hand, when liquid leakage occurs, the liquid is absorbed by the external braided body made of liquid-absorbing threads, and the liquid is efficiently spread to the surrounding area by capillary action, so that the liquid leakage occurs between the conductors. Even if the distance is long, the leakage liquid efficiently penetrates the internal braided body, so the resistance value between the conductors decreases, and the occurrence of liquid leakage is detected by a measuring device connected to the conductor.

[0007] Furthermore, since one of the conductors is coated on the plastic optical fiber, the cross-sectional area of the detection line can be made smaller than when it is provided separately.

[0008]

[Embodiments] The present invention will be described in detail below based on embodiments shown in the drawings.

[0009] FIG. 1 is a cross-sectional view of a temperature/liquid leakage detection line according to an embodiment of the present invention.

[0010] The temperature leakage detection wire 20 of this embodiment is a pair of first and second linear bodies 22, 24 twisted together.
The first linear member 22 is configured by covering a single plastic optical fiber 26 with a conductor 28 made of a metal braid, and further covering the conductor 28 with an inner braid 30 in that order.
The second linear body 24 is formed by covering an inner braid 34 on a conductor 32 made of, for example, a plurality of tin-plated soft copper wires twisted together.

[0011] The plastic optical fiber 26 is made of a material that has excellent bending resistance and has the property of softening and shrinking in a certain temperature range when heated, such as methacrylic resin and polystyrene resin. A fiber wire 16 made of a highly flexible core 12 coated with a low refractive index cladding 14 made of fluororesin or the like is coated with a protective layer 18 made of black polyethylene or the like. A cable core 25 made by twisting the first and second linear bodies 22 and 24 is covered with an external braided body 36 made of a liquid-absorbing thread, for example, a multifilament Tetoron thread. Note that the internal braided body 30,
As the thread 34, for example, a braided body made of monofilament polyethylene thread is used.

[0012] If the temperature/liquid leakage detection line 20 having the above configuration is arranged on the object to be detected, as a result of overheating of a part of the object to be detected, the plastic optical fiber 26,
When the temperature of 42 reaches the softening temperature or higher, the overheated portion softens, contracts, and breaks. As a result, the optical signal from the light source is no longer transmitted midway through, and a photodetector connected to the plastic optical fiber 26 detects the abnormality. On the other hand, when liquid leakage occurs, the resistance value between the conductors 28 and 32 decreases, so that a measuring instrument connected to the conductors 28 and 32 detects the occurrence of liquid leakage.

[0013]

[Effect of the invention] As described above, according to the invention,
A first linear body formed by coating a conductor and an internal braided body on a plastic optical fiber, and a second linear body formed by coating a conductive body with an internal braided body,
It is coated with an external braided body made of liquid-absorbing threads and
Since it constitutes a liquid leakage detection line, there is no need to install a fire sensor and a liquid leakage sensor separately as in the past.
Both the occurrence of fire and the occurrence of liquid leakage can be reliably detected using only this temperature/liquid leakage detection line.

[0014] Therefore, if a temperature/liquid leakage detection line is installed inside a building or equipment, and a photodetector, resistance meter, alarm, etc. is connected to this, temperature and liquid leakage can be detected. It is possible to configure a detection system that also serves as anomaly detection.
Installing sensors is also advantageous, and the cost of disaster prevention equipment can be reduced, making it useful for fire and flood prevention.

[0015] In particular, in this structure, since the periphery of the plastic optical fiber and the outer periphery of both linear bodies are formed by the braided body, good air permeability between the outside and the optical fiber is maintained, and temperature and When at least a part of the object to be detected where the leak detection wire is installed becomes overheated and the temperature of the surrounding air rises, the surrounding air is smoothly guided to the optical fiber part, and the temperature rise is immediately absorbed by the plastic. The temperature is transmitted to the optical fiber, thereby allowing abnormal temperature detection to be performed quickly and with high accuracy.

[0016] Furthermore, since the external braided body is made of liquid-absorbing yarn, in the event of liquid leakage, the leaked liquid is efficiently absorbed by the external braided body, and the liquid is absorbed by capillary action. The liquid spreads efficiently to the surrounding area, and even when the distance between the conductors is large, the leakage liquid is introduced efficiently and the resistance value between the conductors decreases, so the occurrence of liquid leakage can be detected quickly and accurately. That will happen.

Furthermore, since one of the conductors is coated on the plastic optical fiber, the cross-sectional area of the detection wire can be made smaller than when it is provided separately.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of the present invention.

[Explanation of symbols]

20...Temperature/liquid leakage detection line 22, 24...first and second linear bodies 26...optical fiber 28, 32... conductor 30, 34... Internal braided body 36...External braided body.

Claims (2)

[Scope of utility model registration request] 1. A first linear body and a second linear body are covered with an external braided body made of liquid-absorbing thread, wherein the first linear body is made of plastic. The optical fiber is constructed by sequentially covering an electric conductor made of a metal braided body and an inner braided body made of a synthetic fiber yarn, and the second linear body is coated with an inner braided body made of a synthetic fiber yarn on the conductor. A temperature/leakage detection wire characterized by being constructed by covering the body. 2. The temperature/leakage detection wire according to claim 1, wherein the synthetic fiber yarn constituting each of the internal braided bodies is a monofilament polyethylene yarn.